Smoke from around the region affecting Ukiah air quality

Smoke from several fires south and east of Mendocino County are causing haze and poor air quality after a recent wind shift, according to the Mendocino County Air Quality Management District.

Air Pollution Control Officer Bob Scaglione was preparing Monday afternoon to issue an air quality warning telling Inland Mendocino County residents that the air quality has dropped into the "Unsafe for Sensitive Groups" category on the state's Air Quality Index.

"We're getting smoke from several fires," Scaglione said, adding that while smoke from Oregon fires had been hanging in the air, the haze that started to build Sunday was from smoke drifting north and west from fires in Butte, Placer, and Tuolumne and Calaveras counties.

The weather pattern that's bringing the smoke from points south and east is expected to continue through Wednesday morning, according to Scaglione.

One of the major contributors is a blaze that had consumed about 2,000 acres just south of Oroville and was 45 percent contained by midday Monday, he said. Others included a fire that had grown to 13,750 acres in the Tahoe National Forest, a fire of about 800 acres in the Stanislaus National Forest and a smaller fire in Calaveras County.

Residents who have respiratory disease, heart conditions and the elderly are most vulnerable to the air quality conditions, according to Scaglione, and are urged to stay indoors or to limit outdoor activities.

On the state's AQI scale, Ukiah's air quality was 117 early Monday afternoon, and Willits' was 112. Good air quality on the AQI is anything up to 50; up to 99 is "moderate;" and 100 and higher is "Unhealthy for Sensitive Groups."

Good news may be on the horizon, however, according to Scaglione, as the air isn't stagnant during the day.

"We've got a pretty good breeze, and we have enough air movement," he said.

Temperature inversions can set in at night, he added, when the hot air in the bowl of the Ukiah Valley can't rise above the cooler air, and the smoky air can get trapped at the lower levels.

Tiffany Revelle can be reached at udjtr@ukiahdj.com, on Twitter @TiffanyRevelle or at 468-3523.